here are some basics for computer troubleshooting

when windows is not loading or you are having trouble uninstalling viruses or spyware or any program. follow these steps
1. during boot up press F8..it will bring you to the advanced boot options. Select Safe mode. (this loads only the bare minimum to boot and run. there is no internet function and your graphics will be reverted to its lowest setting) if internet is needed select Safe mode with network support.

once in there you can troubleshoot your system fairly easily. (just remember your AV and firewall will not be loaded so tread carefully)

if you computer boots and your having problems getting into safe mode
click on run in the start menu (vista users can type msconfig in the search ..right click and run administrator) at the run menu type in msconfig.
a new window will open and will have these tabs on the top (general, system.ini,boot.ini,services,startup,tools) select the boot.ini
then under the boot options select "/SAFEBOOT" you can select network radio button if you want network support.

Another great feature that i will use when repairing/mat. or troubleshooting is go to the run menu. type cmd.
then type in sfc /scannow within the command prompt window...this is the system file checker utility. it will scan all of your system files and repair corrupted or missing files ( MAKE SURE YOU HAVE YOUR WINDOWS INSTALL CD IN YOUR CD DRIVE!!!)

for vista users ..under the search tile..type cmd...right click on the cmd.exe and select run as administrator...then type in sfc /scannow in the prompt